The purpose of the study is to assess the effect of an early and complete correction of anemia after treatment with epoetin alfa on the rate of progression of chronic renal failure (which involves improper functioning of the kidneys). It also assesses the effect of hemoglobin normalization (correction of anemia) on the need for renal (kidney) replacement therapy, quality of life, blood pressure control, hospital admissions, mortality, cardiovascular events, nutritional status and safety.